Epidemiological Surveillance And Control Of Classical Swine Fever In Some Pig Herds In Henan Provine

Classical swine fever(CSF), caused by classical swine fever virus(CSFV), is an important, potent, highly contagious and fatal disease for swine with widespread economic losses. Strict control measures had been adopted in the world, while the disease is still uninterrupted prevalent in China although legal measures for compulsory vaccination had also been taken. Classical swine fever epidemic situation is quite complicated in Henan. In present study author analyzed the swine fever virus proteins E0 and E2;detected CSFV gene with the RT-PCR and counted the CSF antibodies in part of farm of Henan province;and make the control programm for the CSFV in Henan province. 1 Analysis of CSFV E2 gene and E0 geneIn order to study on the genetic variation of classical swine fever, This study genotyped the E2 gene and E0 gene of CSFV strains isolated during 2013–20104 from domestic pigs in different farm of Henan province. Outcome is that homology of E0 gene of CSFV isolated Henan is extremely high, and the E0 gene of CSFV strains isolated Henan is far from the classical strains shimen strain and vaccine strains HCLV. Phylogenetic analyses revealed that all of the 5 CSFV isolates were clustered into genetic subgroup 1 and 2. Furthermore, the positive selection pressures acting on the Erns and E2 envelope protein genes of CSFV were assessed and a site-by-site analysis of the d N/d S ratio was performed to identify specific codons that undergo diversification under positive selection. While no significant evidence for positive selection was observed in E0 and E2. In addition to this,I analysis of E2 gene of CSFV isolated Henan and discovered a mutation of glycosylation sites. 2 Detection of CSFV samples from Henan province with RT-PCRThe 226 copies of suspected diseased, CSFV,were detected with the reverse transcription-polymerase chain reaction(RT-PCR) method, which were collected from 185 pig farms in Henan Province. Outcom is that the onset of CSF in winter is higher than other three seasons. 3 Some of Henan farms’ antibodies immune monitoringBy enzyme-linked immunosorbent assay(ELISA) for swine fever antibodies, 2365 serum samples were collected from part of farm of Henan from January 2014 to January 2015. The results show that the antibodies about sow, piglet, nursery pig, finishing pig, gilts, bore is 80.0%、66.4%、52.9%、64.1%、78.9%、92.4%.The immune effect of CSF is poor. 4 The development and application of comprehensive prevention and control measuresBased on the above findings, Integrated prevention and control measures were initial taken in 1 pig farm of Henan Province. Including bio-security, vaccination, Immunoassay, medicines, and based on antibody, pathogen detection and production results ultimately. We provided some help about controlling the disease and stable production in pig farm. The measures laied foundation for control of CSFV.